John Robert Isner (born April 26, 1985) is an American professional tennis player. He achieved his career-high singles ranking of world no. 9 on April 16, 2012, and is currently the highest-ranked male American tennis player. In 2013, he became the 18th player to serve more than 5000 aces. He currently has the 17th most aces in the history of the ATP, having served more than 5100 aces. At the 2010 Wimbledon Championships, he played the longest professional tennis match in history, defeating Nicolas Mahut in a total of 11 hours and 5 minutes of play over the course of three days. He also played in then-10th (in singles) longest match - a 5 hour 41 minute encounter in the second round of the 2012 French Open.